Many attempts have been made for template removal from inorganic porous materials at mild temperature (below 350 degrees C), because high-temperature calcination is attributed as the trigger of the framework damages. In this study, a new two-step method, coupling by low-temperature hydrocracking and oxidation, is proposed for efficient removal of the organic templates in high-silica MFI zeolite crystals of different size at a mild temperature (300 degrees C). With this approach, unlike in conventional calcination above 400 degrees C, the pristine zeolite framework is preserved and no coke-like residues are formed, consistently verified by NMR, TGA, and Raman spectra. The reason for this phenomenon is proved as a special propyl-radical-mechanism in H-2 atmosphere, indicated by GC measurement and analysis online. This provides an alternative option for the low-temperature detemplation of high-silica microporous materials. (C) 2016 Elsevier Inc. All rights reserved.